1) Field of the Invention
The present invention relates to the use of a human hepatoma up-regulated protein (HURP) gene as a molecular marker in the detection, preliminary screening or monitoring of bladder cancer in a human subject, in which the detected expression of the human HURP gene in a sample taken from a human subject suspected to have bladder cancer is indicative of the presence of the bladder cancer. The present invention thus provides an efficient method for the detection of bladder cancer, in particular transitional cell carcinoma (TCC) of the bladder, in a human subject. The present invention further provides a non-invasive method for the detection, preliminary screening or monitoring of urinary TCC in a human subject with high accuracy and convenience, in which a urine sample taken from a suspected human subject is analyzed to determine an expression of the human HURP gene, the presence of which is indicative of the presence of urinary TCC.
2) Description of the Related Art
Urothelial carcinoma is the second most common malignancy of the genitourinary tract and is also the second leading cause of death among all genitourinary tumors (Konety B R and Getzenberg R H: Urine based markers of urological malignancy. J Urol 165: 600–611, 2001). Transitional cell carcinoma (TCC) of the bladder is responsible for more than 90% of urothelial neoplasms and it either presents as papillary superficial lesions with low malignant potential or high grade tumors that can be invasive and lethal. When bladder cancer is detected early during a localized stage, the 5-year survival rate is 94%. Once the disease has spread regionally or distally, the 5-year survival rate drops to 49% and 6%, respectively (Droller M J: Individualizing the approach to invasive bladder cancer. Contemp. Urol., July/August, pp. 54–61, 1990). It is thus important to detect the early events in the recurrence of superficial cancer before the cancer cells have time to change their behavior to invasive.
Classical cytology and cystoscopy under scheduled follow-up protocols are the main methods for the surveillance of patients with urinary TCC. The low sensitivity for low-grade tumor using voided urine cytology requires the frequent use of invasive cystoscopy, thus eliciting the associated discomfort and the potential risk of infection by urethral instrumentation during cystoscopy. The development of a sensitive noninvasive diagnostic test that could specifically detect bladder carcinoma in the early stages would improve the clinical outcomes by starting the treatment earlier.
U.S. Pat. No. 6,376,188, entitled “Method and probe set for detecting cancer,” U.S. Pat. No. 6,251,638, entitled “Methods for detection of nucleic acid sequences in urine,” and U.S. Pat. No. 6,287,820, entitled “Methods for protection of nucleic acid sequences in urine,” disclosed the diagnosis of bladder cancer using sets of chromosomal probes to detect a urine sample, respectively.
U.S. Pat. No. 6,335,167, entitled “Comparative genomic hybridization (CGH),” disclosed the diagnosis of bladder cancer by detecting nucleic acid sequence copy numbers, in particular detecting an amplification of a unique sequence at least one position selected from the group consisting of q21 on human chromosome 8, q31-qter on human chromosome 13, p15-pter on human chromosome 7, q24-qter on human chromosome 8, cen-p13 on human chromosome 11 and q13-qter on human chromosome 9, in the test sample.
U.S. Pat. No. 6,291,163, entitled “Method for detecting cell proliferative disorders,” disclosed the diagnosis of cancer (including bladder cancer) and pre-cancer in a subject, by detection of nucleic acid sequence, the features of which reside in the following steps: (a) amplifying test sample DNA at a genetic locus for which the subject is heterozygous, wherein the genetic locus comprises first and second alleles, said genetic locus comprising microsatellite DNA, wherein the test sample DNA is from a cell of an organ which drains into the test samples, wherein the test sample is selected from the group consisting of the subject's: urine, sputum, bile, stool, saliva, tears, serum and plasma; and (b) detecting an allelic imbalance at the genetic locus by determining and comparing level of microsatellite DNA present at the first allele to level of microsatellite DNA present at the second allele, wherein an allelic imbalance is indicative of cancer or precancer.
WO 01/86288, entitled “Method and apparatus for early diagnosis of bladder tumor in urine samples,” disclosed a method for early diagnosis of bladder tumor in a urine sample, which comprises a step of amplification of the RNA extracted from cells present in the urine by using a marker for the messenger RNA of the catalytic component of telomerase (hTRT), a marker for β-actin to demonstrate RNA accessibility and as standard for quantitative estimation, in combination with at least one additional marker chosen from the group that comprises: a marker for a protein of the cytokeratin family, and a lymphocyte marker which is suitable to detect inflammatory cells associated with neoplastic infiltration, and a final step of detecting the amplified material.
WO 99/63110, entitled “Diagnosis and treatment of cancer,” disclosed a method of diagnosing bladder cancer in a human patient comprising the steps of (i) obtaining a sample containing nucleic acid and/or protein from the bladder of a patient, preferably from the urothelium; and (ii) determining whether the sample contains a level of Pax 5 nucleic acid or protein associated with bladder cancer.
WO 02/27329, entitled “Biomarkers of transitional cell carcinoma of the bladder,” disclosed protein markers, methods and kits that can be used as an aid for diagnosis of transitional cell carcinoma of the bladder (TCC) using markers that are differentially present in the samples of TCC patients and a control (e.g., subjects in whom TCC is undetectable).
U.S. Pat. No. 6,335,170 disclosed a method for determining an expression pattern of a urothelium or bladder cancer cell, comprising: determining expression of one or more genes in a sample comprising urothelium or bladder cancer cells, whereby a first pattern of expression is formed; subtracting from the first pattern of expression a second pattern of expression, wherein the second pattern was formed using the one or more genes and a sample comprising predominantly submucosal, smooth muscle, or connective tissue cells, said step of subtracting forming a third pattern of expression which reflects expression of the urothelium or bladder cancer cells independent of the proportion of submucosal, smooth muscle, or connective tissue cells present in the sample.
Other relevant studies directed to bladder cancer include: Konety B R and Getzenberg R H: Urine based markers of urological malignancy. J Urol 165: 600–611, 2001; Droller M J: Individualizing the approach to invasive bladder cancer. Contemp. Urol., July/August, pp. 54–61, 1990; Nomura N, Miyajima N, Sazuka T, et al: Prediction of the coding sequences of unidentified human genes. I. The coding sequences of 40 new genes (KIAA0001–KIAA0040) deduced by analysis of randomly sampled cDNA clones from human immature myeloid cell line KG-1. DNA Res 1: 27–35, 1994; Bassal S, Nomura N, Venter D, et al: Characterization of a novel human cell-cycle-regulated homologue of Drosophila dIg1. Genomics 77: 5–7, 2001; Ellis W J, Blumenstein B A, Ishak L M, et al: Clinical evaluation of the BTA TRAK assay and comparison to voided urine cytology and the Bard BTA test in patients with recurrent bladder tumors. The Multi Center Study Group. Urology 50: 882–887, 1997; Sarosdy M F, Hudson M A, Ellis W J, et al: Improved detection of recurrent bladder cancer using the Bard BTA stat Test. Urology 50: 349–353, 1997; Seripa D, Parrella P, Gallucci M, et al: Sensitive detection of transitional cell carcinoma of the bladder by microsatellite analysis of cells exfoliated in urine. Int J Cancer 95: 364–369, 2001; Ponsky L E, Sharma S, Pandrangi L, et al: Screening and monitoring for bladder cancer: refining the use of NMP22. J Urol 166: 75–78, 2001; Konety B R, Nguyen T S, Dhir R, et al: Detection of bladder cancer using a novel nuclear matrix protein, BLCA-4. Clin Cancer Res 6: 2618–2625, 2000; Rotem D, Cassel A, Lindenfeld N, et al: Urinary cytokeratin 20 as a marker for transitional cell carcinoma. Eur Urol 37: 601–604, 2000; Sanchez-Carbayo M, Urrutia M, Gonzalez de Buitrago J M, et al: Evaluation of two new urinary tumor markers: bladder tumor fibronectin and cytokeratin 18 for the diagnosis of bladder cancer. Clin Cancer Res. 6: 3585–3594, 2000; Sanchez-Carbayo M, Urrutia M, Silva J M, et al; Urinary tissue polypeptide-specific antigen for the diagnosis of bladder cancer. Urology 55: 526–532, 2000; Smith S D, Wheeler M A, Plescia J, et al: Urine detection of survivin and diagnosis of bladder cancer. JAMA 285: 324–328, 2001.
However, to our knowledge, none of the above cited references have reported the expression of a human HURP gene in bladder cancer or urothelial cancer. It is surprisingly found by the applicant that TCC tissue samples displayed reproducible and significant expression of HURP mRNA transcripts. Based on this finding, it is possible to develop an accurate, convenient and noninvasive diagnostic method for the detection, preliminary screening or monitoring of bladder cancer in a human subject by analyzing the expression of a human HURP gene in a biological sample, such as tumor tissue samples and voided urine, the detected expression of the human HURP gene being indicative of the presence of the bladder cancer.